Various methods and apparatus have been devised for protecting the ears from the elements, heat, cold and/or wind. As an alternative to hats or hoods that cover both the head and the ears, earmuffs are often used when a protective covering is desired for the ears, but not for the head. Earmuffs also may be used in combination with hats or hoods when additional protection is desired for the ears. However, earmuffs generally require a band that is placed over the top of the head, or around the back of the head and/or neck, to connect the two earmuffs and keep them in place over the ears (see, for example, U.S. Pat. No. 6,880,174 to Prokop, which is incorporated herein by reference in its entirety).
Bandless earmuffs (i.e., earmuffs without a band over the top, or around the back, of the head/neck), or ear protectors, have been devised that engage the ear directly for maintenance without additional external support. These bandless earmuffs often comprise one of two basic designs: a bistable, truncated cone for reversibly clamping the ear, or an elastic band that may be stretched for placement over the ear. Bistable truncated cone designs are described, for example, in U.S. Pat. Nos. 2,325,150 to Sahlmann; 2,378,398 to Fiedler; 3,112,493 to Greenberg; 4,713,843 and 4,872,219 to Duncan; 5,339,467 to Brinkley; 5,898,945 to Weiser; and 6,055,672 and 7,006,649 to Natvig, all of which are incorporated herein by reference in their entireties. Elastic band designs are described, for example, in U.S. Pat. No. 5,778,455 to Joseph, and U.S. Pat. No. 6,298,493 to Ambroise, both of which are incorporated herein by reference.
With reference to the bistable truncated cone designs, the bandless earmuffs generally comprise an annular segment of a rigid or semi-rigid material, such as plastic cut from a sheet, that is formed into a bistable truncated cone, e.g., by cutting the annular segment to create two edges (e.g., creating a “C”-shaped segment) that are approximated and/or overlapped and secured, or by thermoforming the annular segment into the truncated cone shape. Alternatively, the bistable truncated cone may be formed directly via injection molding. The truncated cone is bistable, such that it may be everted from a concave to a convex configuration.
While in the convex configuration, the truncated cone is configured for passage over an external ear, such that the cone may be placed against a cranial (i.e., back or inner) surface of the ear without substantially deforming the truncated cone. An outer covering is coupled to the bistable truncated cone for covering a lateral (i.e., front or outer) surface of the external ear, thereby forming a bandless earmuff. While the cone is in its stable convex configuration, a chamber or space is formed between the outer covering and the bistable truncated cone, which facilitates passage of the external ear through the opening in the truncated cone into the chamber. After placement of the ear within the chamber, the truncated cone may be flexed to evert the cone to its stable concave configuration, thereby clamping the ear between the cone and the outer covering and securing the bandless earmuff to the ear without additional external support.
With reference to the elastic band designs, a pouch of flexible material is formed for placement over the ear. All or a portion of the opening of the pouch may be attached to an elastic band and/or may be wrapped around the elastic band and secured, e.g., sewn or glued, to itself, such that the elastic band is positioned within a pocket about all or a portion of the perimeter of the pouch's opening. When the elastic band is formed into a loop with its ends attached to one another, the elastic band may, or may not, be attached to the flexible material of the pouch, e.g., at or near its attached ends. When the elastic band is not formed into a loop, the elastic band may be attached to the flexible material at least at or near its ends.
In an unstressed configuration, the elastic band generally has a linear length that is less than the unstressed linear length of the pouch opening (or the portion of the pouch opening that it circumscribes). As such, the flexible material of the pouch generally is bunched locally to provide additional material to facilitate elastic deformation of the elastic band to reversibly enlarge the opening of the pouch for placement of the ear within the pouch. After placement of the ear within the pouch, the elastic band shortens, which reduces the size of the pouch opening and engages the ear to maintain the pouch over the ear.
While both bistable truncated cone designs and elastic band designs reversibly engage the ear and may be utilized to secure bandless earmuffs to the ear, each has drawbacks. In the secured concave configuration of the bistable truncated cone designs, the ear may be clamped between the cone and the outer covering with substantial force to ensure that the cone is maintained in the concave configuration and to form a secure clamp. While effective, this clamping mechanism may be uncomfortable since the ear is continuously squeezed, often for an extended period of time. Furthermore, since the opening in the truncated cone is of generally fixed perimeter geometry and size, the cone may not be configured for passage over a large range of ear sizes and/or the relatively rigid edge of the truncated cone's opening may uncomfortably abut the ear root. Alternatively, the truncated cone may clamp the ear at or near its helix, leaving a portion of the ear unprotected along its cranial surface between the ear root and the edge of the truncated cone and enhancing a risk of the ear protector sliding off the ear due to instability and insufficient clamping.
In the elastic band designs, the localized bunching and additional pouch material necessary to facilitate expansion of the pouch opening for placement of the pouch around the ear may provide a profile during use that is unsightly, unfashionable and/or is not streamlined. Furthermore, the elastic band and/or the bunched pouch material may uncomfortably impinge on the ear root and/or may apply stress to the ear root non-uniformly with uncomfortable areas of stress concentration. Furtherstill, the localized bunching of the pouch material and/or the limited elasticity of the elastic band may preclude use of some pouch materials possessing desirable thermal characteristics, for example, due to the thickness and/or relative resilience of such materials.
In view of the foregoing, it would be desirable to provide methods and apparatus for ear protection that overcome the drawbacks of previously known methods and apparatus.